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921.
Three-dimensional porous nitrogen-doped graphene aerogels (NGAs) were synthesized by using graphene oxide (GO) and chitosan via a self-assembly process by a rapid method. The morphology and structure of the as-prepared aerogels were characterized. The results showed that NGAs possesed the hierarchical pores with the wide size distribution ranging from mesopores to macropores. The NGAs carbonized at different temperature all showed excellent electrochemical performance in 6 mol/L KOH electrolyte and the electrochemical performance of the NGA-900 was the best. When working as a supercapacitor electrode, NGA-900 exhibited a high specific capacitance (244.4 F/g at a current density of 0.2 A/g), superior rate capability (51.0% capacity retention) and excellent cycling life (96.2% capacitance retained after 5000 cycles). 相似文献
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Gang Bi Wei Xiong Li Wang Kosei Ueno Hiroaki Misawa Jian-rong Qiu 《Optics Communications》2012,285(9):2472-2477
This paper presents optical property of the periodical bowties structure of Au nanoparticles on glass substrate fabricated by high-resolution electron beam lithography. Numerical calculation is used to examine the shape-induced surface plasmon enhancement and extinction spectroscopy by using Finite-Difference Time Domain algorithm and Lorentz model of surface plasmon. The calculated extinction spectra of the periodical nanoparticles are consistent with the experimental results. The influence of the geometrical shape on the spectral properties of bowtie nanoparticles is discussed. This investigation may help one to design plasmonic sub-wavelength devices with desired spectral properties. 相似文献
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Xu Zhao Zhimin Long Jinna Dai Kaishun Bi Xiaohui Chen 《Rapid communications in mass spectrometry : RCM》2012,26(20):2443-2453
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Making several components be more intimate interfacial contacts in the photocatalyst is an efficient strategy to improve the separation and transfer of photogenerated charge carries and enhance the photocatalytic performance in the visible light region. In this work, a promising photocatalyst was fabricated by loading of Au nanoparticles and Cd(0.58)Zn(0.42)S nanoparticles onto the three dimensionally ordered mesoporous g-C3N4 material (Au/3DOM CN/Cd(0.58)Zn(0.42)S) via two-step synthesis method to significantly intensify the transfer capability of charge. The results of characterization demonstrate that Au/3DOM CN/Cd(0.58)Zn(0.42)S photocatalyst possesses the intimate interfacial contacts of three components and homogeneous wall thickness of 3DOM g-C3N4 framework, and these properties give Au/3DOM CN/Cd(0.58)Zn(0.42)S photocatalyst an ability that it can harvest a wider range of visible light and endow it superior photocatalytic activities for hydrogen evolution from water splitting and RhB degradation. Finally, a possible mechanism was proposed based on the photoelectrochemical measurement. This work would provide a new strategy to design and fabricate g-C3N4-based with 3DOM architecture materials with superior photocatalytic activity. 相似文献
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